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A natural holm oak forest was selectively thinned to test thinning as a tool to reduce tree mortality, increase productivity, and reverse the recent regression of the dominant species (Quercus ilex) induced by climate change. Thinning increased aboveground productivity and reduced stem mortality in this Mediterranean forest during four years just after thinning, contributing to the maintenance of forest functioning under changing climatic conditions. Q. ilex was the only species positively affected by the thinning: stem growth increased for all stem sizes, and mortality was significantly lower in thinned plots. On the contrary, mortality rates of Phillyrea latifolia and Arbutus unedo were not significantly lower. Stem growth increased for P. latifolia only in the smallest stem-size class. Our results highlight the suitability of selective thinning for improving the forest productivity and ensuring the conservation of Mediterranean coppices. Other benefits of selective thinning, such as a decrease in the risk of fire dispersion and an increase in the water supply for human populations, are also discussed.

It is increasingly acknowledged that climate change is influencing terrestrial ecosystems by increased drought and rainfall intensities. Soil microbes are key drivers of many processes in terrestrial systems and rely on water in soil pores to fulfill their life cycles and functions. However, little is known on how drought and rainfall fluctuations, which affect the composition and structure of microbial communities, persist once original moisture conditions have been restored. Here, we study how simulated short-term drying and re-wetting events shape the community composition of soil fungi and prokaryotes. In a mesocosm experiment, soil was exposed to an extreme drought, then re-wetted to optimal moisture (50% WHC, water holding capacity) or to saturation level (100% WHC). Composition, community structure and diversity of microbes were measured by sequencing ITS and 16S rRNA gene amplicons 3 weeks after original moisture content had been restored. Drying and extreme re-wetting decreased richness of microbial communities, but not evenness. Abundance changes were observed in only 8% of prokaryote OTUs, and 25% of fungal OTUs, whereas all other OTUs did not differ between drying and re-wetting treatments. Two specific legacy response groups (LRGs) were observed for both prokaryotes and fungi. OTUs belonging to the first LRG decreased in relative abundance in soil with a history of drought, whereas OTUs that increased in soil with a history of drought formed a second LRG. These microbial responses were spread among different phyla. Drought appeared to be more important for the microbial community composition than the following extreme re-wetting. 16S profiles were correlated with both inorganic N concentration and basal respiration and ITS profiles correlated with fungal biomass. We conclude that a drying and/or an extreme re-wetting history can persist in soil microbial communities via specific response groups composed of members with broad phylogenetic origins, with possible functional consequences on soil processes and plant species. As a large fraction of OTUs responding to drying and re-wetting belonged to the rare biosphere, our results suggest that low abundant microbial species are potentially important for ecosystem responses to extreme weather events.

The Nigerian government is committed to sustaining rice production to meet national demand. Nevertheless, political tension and climate-induced stressors remain crucial constraints in achieving policy targets. This study examines whether climate change and political instability significantly threaten rice production in Nigeria. First, we employed nonparametric methods to estimate the country's rainfall and temperature trends between 1980Q1 and 2015Q4. Second, we employed the autoregressive distributed lag (ARDL) technique to examine the effects of climate change and political instability on rice production. The results show that while temperature has an increasing pattern, rainfall exhibits no significant trend. The findings from the ARDL estimate reveal that rice production responds negatively to temperature changes but is less sensitive to changes in rainfall. In addition, political instability adversely affects rice production in Nigeria. We argue that Nigeria's slow growth in rice production can be traced back to the impact of climate change and political tension in rice farming areas. As a result, reducing the overall degree of conflict to ensure political stability is critical to boosting the country's self-sufficiency in rice production. We also recommend that farmers be supported and trained to adopt improved rice varieties less prone to extreme climate events while supporting them with irrigation facilities to facilitate rice production.

Heat stress is a global issue constraining pig productivity, and it is likely to intensify under future climate change. Technological advances in earth observation have made tools available that enable identification and mapping livestock species that are at risk of exposure to heat stress due to climate change. Here, we present a methodology to map the current and likely future heat stress risk in pigs using R software by combining the effects of temperature and relative humidity. We applied the method to growing-finishing pigs in Uganda. We mapped monthly heat stress risk and quantified the number of pigs exposed to heat stress using 18 global circulation models and projected impacts in the 2050s. Results show that more than 800 000 pigs in Uganda will be affected by heat stress in the future. The results can feed into evidence-based policy, planning and targeted resource allocation in the livestock sector.

SYNOPSIS In Swaziland policies to alleviate fuelwood shortages have been low on the list of development priorities, as much of the land has extensive bush and tree cover. There are, however, major social and geographical imbalances in biomass resource supply—some areas of Swazi Nation Land are barren due to increasing population pressure and the subsequent demand for fuelwood. This paper will show, in detail, the methodology for the survey which was carried out in Swaziland to investigate the importance of accessibility in linking potential supply to demand. Physical location, land tenure and management practices are generally recognised as important factors to take into consideration when converting potential resources into realistic amounts of fuelwood supply. Guesswork, however, is often used to estimate the impacts of these factors on biomass supplies. A nation-wide study was made in order to obtain more information on the accessibility of resources on privately owned land; results of a household surv...

The lignocellulosic C4 perennial crop miscanthus and, more particularly, one of its species, Miscanthus × giganteus, are especially interesting for bioenergy production because they combine high biomass production with a low environmental impact. However, few varieties are available, which is risky due to disease susceptibility. Gathering worldwide references, this review shows a high genotypic and environmental variability for traits of interest related to miscanthus biomass production and composition, which may be useful in breeding programs for enhancing the availability of suitable clones for bioenergy production. The M. × giganteus species and certain clones in the Miscanthus sinensis species seem particularly interesting due to high biomass production per hectare. Although the industrial requirements for biomass composition have not been fully defined for the different bioenergy conversion processes, the M. × giganteus and Miscanthus sacchariflorus species, which show high lignin contents, appear more suitable for thermochemical conversion processes. In contrast, the M. sinensis species and certain M. × giganteus clones with low lignin contents were interesting for biochemical conversion processes. The M. sacchariflorus species is also interesting as a progenitor for breeding programs, due to its low ash content, which is suitable for the different bioenergy conversion processes. Moreover, mature miscanthus crops harvested in winter seem preferred by industry to enhance efficiency and reduce the expense of the processes. This investigation on miscanthus can be extrapolated to other monocotyledons and perennial crops, which may be proposed as feedstocks in addition to miscanthus.